Heat engines are known to operate on differing principles and among which are the Rankine steam cycle, and the Otto and Carnot internal combustion cycles. The Rankine cycle engines are known for their high torque characteristics particularly when starting, while the Otto (gas) and Carnot (Diesel) cycle engines rely upon inertia and require substantial momentum in order to produce high torque. Furthermore, Otto and Carnot cycle engines are either four stroke or two stroke, the latter having its operational limitations, whereas the Rankine cycle engines of the reciprocating type produce full power with each stroke regardless of speed (within practical limits). However, with the present invention, it is a hybrid heat engine cycle that is provided wherein two strokes are involved and essentially two cycles, to be known as the Two Stroke Grow Cycle, it being a general object of this invention to provide a high torque high efficiency heat engine of the internal combustion type.
For the purpose of this invention, pressure volume curves are to be read in light of torque characteristics, it being known that the expansion of steam in a cylinder produces superior torque, as compared with known four and two stroke internal combustion engines. With Otto cycle gas engines the induction of air and fuel must have the proper stoichiometric ratio compressed before spark ignition, and the explosive charge ignites when the crank is at a rotational position of disadvantage at or near Top Dead Center. With Carnot cycle Diesel engines the induction air is compressed and the fuel injected for subsequent burning, and again the charge commences its burn when the crank is at a rotational position of disadvantage at or near Top Dead Center. It is an object of this invention to provide a heat engine cycle wherein air induction and fuel injection is transferred into a cylinder when the down-stroke commences and followed by a burning of fuel approximating the performance of the Rankine cycle with the crank at a rotational position of advantage angularly advanced from Top Dead Center.
With the present invention, a downward acting piston compresses combustion air at one end of the cylinder and which is stored in a transfer chamber and subsequently released into the other end of the cylinder when the piston retracts to receive the compressed combustion air. Fuel is either injected along with the transfer of compressed combustion air as in an Otto cycle arrangement, or is injected after the transfer of compressed combustion air as in a Diesel cycle arrangement. In either arrangement, the crank position of the engine is well advanced away from Top Dead Center when combustion is initiated by spark under heat of compression.
This is a cylinder and piston internal combustion heat engine wherein compression is attained during the power stroke, and wherein intake of combustion air occurs during the exhaust stroke, a two cycle or two stroke engine, it being an object of this invention to provide such an engine with induction air transfer means by which high performance is achieved through torque applied to advanced positioning of the engine crank. It is an object of this invention to compress induction air during the power stroke, and to store compressed induction air during the exhaust stroke. It is also an object of this invention to transfer compressed induction air with or without a fuel admixture into the combustion chamber of the cylinder. It is still another object of this invention to delay ignition for advancement of the piston into a position of great mechanical advantage for the efficient application of torque. And it is also an object of this invention to control induction air compression by supercharging where circumstances require.
The engine of the present invention is a departure from both the Otto (gas) and Carnot (Diesel) cycle concepts and is more analogous to the Rankine (steam) cycle, in that full volume compression and measured fuel injection at the beginning of the power stroke is avoided. Replacing the foregoing is controlled injection as it is disclosed in my U.S. Pat. No. 4,070,998 entitled Compression Ignition Controlled Pressure Heat Engine, issued Jan. 31, 1978. To this end it is an object of this invention to continuously inject fuel in a double acting two cycle engine throughout the most effective portion of the work stroke, and at a controlled rate to support combustion within the cylinder.
An object of this invention is to advantageously employ the constant volume variable potency injectors as disclosed in U.S. Pat. Nos. 3,749,097 and 3,921,599 issued to me on July 31, 1973 and Nov. 25, 1975 respectively. It is by means of these fuel injectors, or like injectors, that controlled fuel burning and cylinder pressures are maintained as may be desired. With this invention a constant volume pump intermixes two liquids and discriminately injects the admixture thereof discretely therefrom and into the engine cylinder at a controlled potency. The injector per se is characterized by its differential pump means which are advantageously employed to acquire structural strength and accurately metered fuel injection.